Linus Torvalds introduced the Linux Kernel 4.5 release. Codename "Blurry Fish Butt"

The final release of Linux Kernel 4.5 was quietly and discreetly presented . Since January 25, 2016, about 7 RC builds have been released, the last one is on March 6 of this year. In the current version, about 13,000 patches from 1500+ developers were made. The total size of the patch is 70 MB, with the changes affecting 11,589 files, over 1 million lines of code have been added. Approximately half (45%) of all changes are related to device drivers.

Among other changes, we should highlight the addition of support for AMD PowerPlay power management technology, which improves the performance of AMDGPU open-source drivers for Radeon graphics adapters, improved allocation of free space in Btrfs, implementation of project quotas in ext4, support for assembly with the inclusion of a detector of uncertain behavior, support for direct correction dm-verity errors, stabilizing the new unified cgroup hierarchy, connecting BPF balancers for UDP sockets in SO_REUSEPORT mode, increasing epoll scalability for multi-thread applications.

Another important change is the new system call copy_file_range. It allows you to significantly speed up the execution of operations to copy data from the source file to another file, and the operation is performed on the kernel side. There is no need to pre-read the data in the memory of the process in user space. However, the acceleration of the user may not be too noticeable, since time is spent reading / writing data for the drive. A different situation will work with NFS partitions.
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A complete list of important updates and changes can be found here (English) or here (Russian).

The source code for the new kernel version can be downloaded from kernel.org.